Title Alternative The origin of infra-slow oscillations of oxygenated hemoglobin observed in functional near-infrared spectroscopy
FullText URL 126_117.pdf
Author Shoshi, Chikafumi| Ueno, Hiroshi| Kubo, Masako| Oda, Masuko| Hirata, Naoya| Takemoto, Rika| Kinugasa, Kazushi| Okamoto, Motoi|
Abstract There is increasing interest in the intrinsic activity of the resting brain, especially the activity slower than 0.1Hz (i.e., low-frequency oscillations, or LFOs). To investigate the origin of LFOs observed in functional near-infrared spectroscopy (fNIRS), we recorded multichannel fNIRS and electroencephalography (EEG) from the frontal cortex of 11 healthy young volunteers in the resting state. Electrocardiography (ECG), electro-oculography and respiration were also measured. Synchronous oscillations of oxy-hemoglobin (oxy-Hb) around 1.0Hz were detected in all fNIRS channels, and their frequency was consistent with a peak frequency of ECG, suggesting the changes of cerebral blood flow due to heart beats. In addition, oxy-Hb oscillations around 0.1Hz (i.e., LFOs) appeared in the fNIRS. The channels where LFOs appeared differed among the subjects, and the LFOs appeared or disappeared even in the same fNIRS channels. The appearance of LFOs in fNIRS channels was significantly higher when the LFOs appeared on the EEG in the adjacent EEG electrodes compared to when LFOs did not appear on EEG. The amplitude and coherence (synchronicity) of the LFOs were increased by changing the subjects' position from dorsal to the sitting position in both fNIRS and EEG, and the coherence in particular was increased in the homologous fNIRS channels on the bilateral hemispheres. These results suggest that LFOs of oxy-Hb couple with resting-state EEG activity.
Keywords fNIRS EEG LFOs コヒーレンス解析(Coherence analysis) 連続ウェーブレット解析(continuous wavelet transforms)
Publication Title 岡山医学会雑誌
Published Date 2014-08-01
Volume volume126
Issue issue2
Start Page 117
End Page 126
ISSN 0030-1558
language 日本語
Copyright Holders Copyright (c) 2014 岡山医学会
File Version publisher
DOI 10.4044/joma.126.117
NAID 130004685262